The following abbreviations that may be found in the specification and/or the drawing figures are defined as follows:
3GPPthird generation partnership projectAPaccess pointBSbase stationCCEcoexistence central entityCCE-PEcoexistence central entity-peer entityCMcoexistence managereNodeBbase station of a LTE/LTE-A systemFCCFederal Communications CommissionIDidentifierIEEEInstitute for Electrical and Electronics EngineersIPInternet protocolISMindustrial, scientific and medicalLTElong term evolution (of the evolved UTRAN system)LTE-Along term evolution-advancedMACmedium access controlRATradio access technologySBD-SNshared band deployment support nodeSSIDservice set identifierTV WStelevision white spacesUEuser equipmentUTRANuniversal terrestrial radio access networkWLANwireless local area network
One approach to preventing congestion of cellular core networks due to the ever-increasing volume of wireless data and number of wireless users is to off-load some wireless traffic to non-cellular networks such as a WLAN, whose access points provide access to the Internet. However, such traffic off-load and anticipated gains from spectrum efficiency improvement is not expected to fully offset predicted data traffic increases. As a result, in addition to the more costly licensed spectrum there is discussion, among radio network operators and manufacturers of user handsets and network equipment, of utilizing license-exempt portions of the radio spectrum for wireless traffic. Such license-exempt spectrum is also termed the shared band or bands, and for example include the ISM band and the TV WS which the FCC in the United States is considering for this use.
In practice, such shared bands may be coordinated by the licensed spectrum systems, or they may be used by a stand-alone cell such as a LTE-A femto cell which provides fast access to the Internet in a similar manner to the WLAN specifications at IEEE 802.11. The advantage of a LTE-A femto cell over the traditional WLAN is the improved spectrum efficiency in LTE-A, realized through such concepts as LTE's flexibility in managing the deployment bandwidth, the number of utilized carriers, and even its flexible reconfiguration of center frequency.
The extension of LTE-A onto the shared band as well as certain problems that are anticipated for such an extension are discussed in a paper by M-A. Phan, H. Wiemann and J. Sachs of Ericsson Research entitled Flexible Spectrum Usage-How LTE Can Meet Future Capacity Demands [ITG FG 5.2.4 workshop, Jul. 8, 2008], and also in a summary of research by Rui Yang of InterDigital Communications LLC entitled Overview of Research Projects with NYU-Poly [Nov. 12, 2010].
One such problem is how to enable co-existence of multiple APs/BSs which deploy into the shared band by efficiently managing the potential interference therebetween. This interference problem exists regardless of whether different APs/BSs are operating on the same or different RATs since it is interference on the shared band which is the concern.
One conventional RAT-independent approach to manage such interference on the TV WS is to use a so-called a coexistence manager (CM), whose architecture is set forth by IEEE 802.19 Task group 1 and shown at FIG. 1. The CM is a function which operates on top of the radio access technologies. It has interfaces to other coexistence manager entities/servers. With the help of the CM, different RATs can negotiate the spectrum utilization between each other or submit to the control of a CM which locally governs the spectrum utilization for the shared spectrum.